In the field of automatic stamping or punching presses, coiled stock material is often fed into a press by a press feeder placed near the front of the press. A common method of feeding the stock material into the press is by passing it through a pair of pinch rollers which apply friction to the material, and rotate in a cooperative manner to feed the stock into the press. By linking the rotation of the pinch rollers to the speed of the press, the stock material is fed into the press at the proper rate.
When a press is performing a punching operation, it is often desirable to align the punched holes as accurately as possible. One method of doing this uses pilot pins in the press which contact the material shortly before the press actually punches the material. The pilot pins are positioned to contact the material in a region where holes have already been punched by the press. The material is advanced to approximately the correct location by the press feeder. More precise positioning of the material then occurs as the pilot pins enter the previously punched holes, and draw them into alignment with the pilot pins. However, for this alignment to take place, the tension applied to the stock material by the pinch rollers of the press feeder must be removed.